Prediction assessments: Using video-based predictions to assess prospective teachers’ knowledge of students’ mathematical thinking

In order to evaluate the effectiveness of an experimental elementary mathematics field experience course, we have designed a new assessment instrument. These video-based prediction assessments engage prospective teachers in a video analysis of a child solving mathematical tasks. The prospective teachers build a model of that child’s mathematics and then use that model to predict how the child will respond to a subsequent task. In this paper, we share data concerning the evolution and effectiveness of the instrument. Results from implementation indicate moderate to high degrees of inter-rater reliability in using the rubric to assess prospective teachers’ models and predictions. They also indicate strong correlation between participation in the experimental course and prospective teachers’ performances on the video-based prediction assessments. Such findings suggest that prediction assessments effectively evaluate the pedagogical content knowledge that we are seeking to foster among the prospective teachers.     

Child sexual abuse and bulimic symptomatology: relevance of specific abuse variables

OBJECTIVE: This study examined specific aspects of child sexual abuse in relation to symptom severity among hospitalized patients diagnosed with bulimia nervosa. METHOD: Participants were 45 hospitalized bulimic women who reported a history of child sexual abuse. Structured interviews were conducted in order to obtain detailed information regarding specific features of the abusive event(s). Participants also completed instruments that measured depression and eating pathology. RESULTS: There were no significant differences in severity of depression or eating disturbance among women reporting differing abusive experiences including intrafamilial versus extrafamilial abuse, abuse with or without the use of physical force, one versus multiple incidents, early abuse versus abuse occurring after age 14, contact versus noncontact abuse, disclosed versus undisclosed, and combined physical/sexual abuse versus sexual abuse alone. CONCLUSION: The specific characteristics of child sexual abuse are not related to the level of symptomatology for hospitalized bulimic patients. This study suggests that differences in the nature of the abuse may not be as important as the fact that the abuse occurred in the first place.     

Mirror-image stimulation and short separations in stumptail monkeys

Two experiments examined the responses of infant stumptail macaques (Macaco arctoides) to mirror-image stimulation (MIS) during short social separations. Overall, infants living in pairs showed agitation when separated from their partners, but were calmer when the partner, an unfamiliar peer, or their own mirror image was visible. MIS elicited more facial expressions than the familiar peer, and more affiliative contact than an unfamiliar peer. In contrast, infants reared in a group were not calmed during separations either by an unfamiliar peer or by MIS, and they exhibited some negative reactions to the mirror. Social responsiveness to MIS varies with the social background of the subjects.     

Effects of heat acclimation on hand cooling efficacy following exercise in the heat

This study examined the separate and combined effects of heat acclimation and hand cooling on post-exercise cooling rates following bouts of exercise in the heat. Seventeen non-heat acclimated (NHA) males (mean ± SE; age, 23 ± 1 y; mass, 75.30 ± 2.27 kg; maximal oxygen consumption [VO₂ max], 54.1 ± 1.3 ml·kg^?1·min^?1) completed 2 heat stress tests (HST) when NHA, then 10 days of heat acclimation, then 2 HST once heat acclimated (HA) in an environmental chamber (40°C; 40%RH). HSTs were 2 60-min bouts of treadmill exercise (45% VO₂ max; 2% grade) each followed by 10 min of hand cooling (C) or no cooling (NC). Heat acclimation sessions were 90–240 min of treadmill or stationary bike exercise (60–80% VO₂ max). Repeated measures ANOVA with Fishers LSD post hoc (α < 0.05) identified differences. When NHA, C (0.020 ± 0.003°C·min^?1) had a greater cooling rate than NC (0.013 ± 0.003°C·min^?1) (mean difference [95%CI]; 0.007°C [0.001,0.013], P = 0.035). Once HA, C (0.021 ± 0.002°C·min^?1) was similar to NC (0.025 ± 0.002°C·min^?1) (0.004°C [?0.003,0.011], P = 0.216). Hand cooling when HA (0.021 ± 0.002°C·min^?1) was similar to when NHA (0.020 ± 0.003°C·min^?1) (P = 0.77). In conclusion, when NHA, C provided greater cooling rates than NC. Once HA, C and NC provided similar cooling rates.     

On Searching for the Latin American Sportswoman and Finding an Argentine Sports Historian

Abstract

This paper is a personal account of the author’s interest in the field of sports history and its emergence in Argentina. It explores several prejudices and misunderstandings that have contributed to a limited and partial vision of this scholarly discipline.     

Broadway productions and the value of a Tony Award

This article investigates the effect of a Tony nomination or win on the demand facing a Broadway production using a panel of weekly revenues for Broadway productions from 1996 to 2007. Our results indicate that the effect of a nomination or win is positive in the week of the announcement and gradually increases in successive weeks, presumably due to publicity and word-of-mouth. Winners experience an increase in demand as late as 1 year later when awards are publicized for the following season. Moreover, nominees that do not win the award are penalized heavily in the weeks following the Award announcements. We find that winning a Tony Award increases a production’s revenues by 12% in the week immediately following the Awards.

Adjacency matrix concepts for the analysis of the interconnection of networks

A mathematical theory is developed for an imagined device termed a “junctor”. A junctor could be used to interconnect two n-terminal networks giving rise to another n-terminal network. Actually a junctor is itself a simple network with three banks of n-terminals internally connected in some fashion by perfectly conducting wires. Adjacency matrices are formulated to analyze various junctors and their current flows. The main problem treated concerns conditions which would ensure that the junctor operation is associative.